/*
* BearLibTerminal
* Copyright (C) 2013 Cfyz
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
* of the Software, and to permit persons to whom the Software is furnished to do
* so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in all
* copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
* FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
* COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
* IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/

#include <stdexcept>
#include <cstring>
#include "LoadBitmap.hpp"
#include "Log.hpp"

// Forward declarations. See LoadXXX.cpp files for definitions.
namespace BearLibTerminal
{
    Bitmap LoadBMP( std::istream &stream );

    Bitmap LoadPNG( std::istream &stream );

    Bitmap LoadJPEG( std::istream &stream );
}

namespace BearLibTerminal
{
    Bitmap LoadBitmap( const std::vector <uint8_t> &data )
    {
        if ( data.size( ) < 4 )
        {
            throw std::runtime_error( "LoadBitmap: invalid data size" );
        }

        unsigned char magic_bytes[4] = { data[ 0 ], data[ 1 ], data[ 2 ], data[ 3 ] };

        // FIXME: rewrite bitmap loading routines. Maybe just use stb_image?
        std::istringstream stream{ std::string(( const char * ) &data[ 0 ], data.size( )) };

        if ( !strncmp(( const char * ) magic_bytes, "\x89PNG", 4 ))
        {
            // This must be PNG resource
            return LoadPNG( stream );
        }
        else if ( !strncmp(( const char * ) magic_bytes, "BM", 2 ))
        {
            // This must be BMP DIB resource
            return LoadBMP( stream );
        }
        else if ( !strncmp(( const char * ) magic_bytes, "\xFF\xD8", 2 ))
        {
            // Must be a JPEG rsource
            return LoadJPEG( stream );
        }
        else
        {
            throw std::runtime_error( "unsupported image format" );
        }
    }
}
